Bette’s Prismatic Blade

You channel light through a diamond (worth at least 50gp) creating a blade of solidified prismatic energy in your hand. This magic sword lasts until the spell ends and counts as a simple melee weapon attack in which you are proficient. You cannot be disarmed.

You choose fire, acid, lightning, poison, cold, thunder, psychic or force for the type of damage and make a melee attack against a creature within 5 feet. On a hit, the target takes the specified damage type equal to 2d8 + your Spellcasting ability modifier.

At Higher Levels: When you cast this spell using a spell slot 5th Level of or higher, the damage increases by 1d8 for every two slot levels above the 3rd.